For nearly 60 years, materials scientists have used ‘Indium tin oxide,’ a transparent film with impurities, to power screens. But the alloy isn’t as efficient as other metals. And as more devices require the magic of ‘ITO’ to power their screens, the price of indium, one of the ‘rare earth metals,’ has skyrocketed. In fact, per gram it’s about twice the price of silver.

But there’s a new alternative. At least, that’s what researcher Roman Engel-Herbert, an assistant professor of materials science and engineering at Penn State University, says.

His team has developed a material that’s both transparent and conductive—a find that could make displays more efficient and affordable within the next three years. Their research, published Monday in Nature Materials, relies on using ‘correlated metals’ made with strontium and calcium, both much cheaper than the traditional indium.

Some of the best conductors are metals (just think of all that copper wiring), but it’s usually difficult to produce them to be see-though, because the thicker they are, the better they conduct. But because of how electrons behave in these correlated metals, the researchers found they’re both swift conductors and extremely transparent.

The next step in the research will be to increase the size of the thin prototypes (the tiny prototypes are currently just 10mm wide) by perfecting the technique for putting the film on surfaces like touchscreen glass.

So smartphones that are cheaper to build isn’t necessarily happening any time soon. But with any luck, in a few years time, the conductive films on screens, TVs, tablets, and even solar panels could be cheaper, thinner, and more efficient, too.

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